Wireless communication networks are widely deployed to provide various communication services such as telephony, video, data, messaging, broadcasts, and so on. Such networks support communications for multiple wireless devices, of potentially numerous different device categories or types. In many cases, a wireless device is a battery-powered device, for which a long battery life is an important concern. One way some devices improve their battery life is by entering a sleep or power saving state for extended periods of time. In this state, various power-hungry components may be shut down, such as a power amplifier, crystal oscillator, etc.
When such a device wakes from the sleep state, and in particular when the sleep state has a long duration, any clock that keeps time at the device may tend to drift, relative to the system time of the rest of the network. Accordingly, the device re-synchronizes with the network to enable communication. This synchronization process generally includes the reception of a synchronization (sync) signal broadcast from a base station and adjustment of clock timing based on the sync signal.
While this sleep and wake up procedure successfully reduces power consumption of mobile devices, there continues to be a need to improve their efficiency and battery life. As the demand for mobile broadband access continues to increase, research and development continue to advance wireless communication technologies not only to meet the growing demand for mobile broadband access, but to advance and enhance the user experience.